The capabilities assembled in the SNP Confirmation and High Throughput Genotyping Core (SNP-Gen Core) provide the Center Investigators (and larger institution) a single point of entry, comprehensive advice (mentoring) for the technical aspects of experiments manipulating nucleic acids, access to highly-trained technical personnel and very sophisticated and expensive equipment. For most, the Core will offer assay development, data collection, or nucleotide synthesis. In some situations advice and education will be obtained. This Core centralizes the equipment and experience needed to efficiently and reliably produce high quality nucleic acid analysis data. The services available through this Core include DMA sequencing, single nucleotide polymorphism (SNP) genotyping, insertion/deletion analysis, tandem repeat genotyping, expression arrays in mouse and man, and SNP arrays. Appropriate internal quality control checks and balances are in place and are outlined in the revised application. The interaction with each of the Center Investigators will be tailored so that the individual training needs of each are met. The core serves to provide data and services efficiently and economically. In some situations massive high throughput data will be generated.